An engine functions between 900°K and T2, while another operates between T2 and 400°K. For both to produce identical work, the value of T2 must be________________?
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Answer: A. 650°K
Explanation
Serial Carnot engines producing equal work output require a specific intermediate temperature calculation. Using harmonic mean temperature principles for equal work output yields 650 Kelvin. This balanced temperature drop ensures identical work contributions from both thermodynamic stages. Thermal efficiency of individual Carnot stages determines their respective work output proportions. Connecting heat engines in series allows sequential extraction of work from thermal energy flows. Absolute temperature scales must be used for all thermodynamic cycle calculations.
Cascaded power generation systems utilize multi-stage thermal cycles to maximize overall energy recovery. Engineers analyze intermediate temperatures to optimize thermal stress distribution across power machinery. Balanced temperature staging improves overall plant reliability and thermodynamic performance. Option B, C, D, and E represent alternative temperature values that fail the equal work output condition. Simple arithmetic averaging does not account for the thermal efficiency ratios of Carnot stages. Rigorous thermodynamic equations confirm 650 Kelvin as the correct intermediate temperature.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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